What is the Difference Between China 5 and China 6 Emission Standards for Vehicles?

[AsherAnn]

The differences between China 5 and China 6 emission standards are as follows: Different Emission Standards: China 6 emission standards are more than 30% stricter than China 5. Excluding the impact of driving conditions and testing, gasoline vehicles' carbon monoxide emissions are reduced by 50%, total hydrocarbons and non-methane hydrocarbons emissions are reduced by 50%, and nitrogen oxide emissions are reduced by 42%. Different Implementation Times: The China 5 standard was implemented nationwide on January 1, 2017. The China 6 standard was implemented on July 1, 2019. Different Principles: Under China 5, diesel and gasoline vehicles had different emission standards. However, China 6 adopts a fuel-neutral principle, meaning the emission limits are the same regardless of the fuel type. Different Issuing Authorities: The China 5 standard was issued by the Ministry of Environmental Protection. The China 6 standard was jointly issued by the Ministry of Environmental Protection and the General Administration of Quality Supervision, Inspection, and Quarantine. Different Letter Representations: China 5 is represented by 'V,' while China 6 is represented by 'VI.' Different Monitoring Requirements for Plug-in Hybrid Electric Vehicles (PHEVs): Compared to China 5, China 6 has enhanced monitoring requirements for PHEVs, including energy storage systems, thermal management systems, brake regeneration, drive motors, generators, and other regulations. China 5 Emission Limits: Gasoline vehicles must not emit more than 1,000 mg of carbon monoxide per kilometer driven. Non-methane hydrocarbons must not exceed 68 mg per kilometer. Nitrogen oxides must not exceed 60 mg per kilometer. PM (particulate matter) must not exceed 4.5 mg per kilometer. China 6 has two standards: China 6a and China 6b. Details are as follows: China 6a Emission Limits: Gasoline vehicles must not emit more than 700 mg of carbon monoxide per kilometer driven. Non-methane hydrocarbons must not exceed 68 mg per kilometer. Nitrogen oxides must not exceed 60 mg per kilometer. PM must not exceed 4.5 mg per kilometer. China 6b Emission Limits: Gasoline vehicles must not emit more than 500 mg of carbon monoxide per kilometer driven. Non-methane hydrocarbons must not exceed 35 mg per kilometer. Nitrogen oxides must not exceed 35 mg per kilometer. PM must not exceed 3 mg per kilometer. Affected by the China 6 emission policy, although China 5 vehicles can still be used normally without restrictions like driving bans or license plate limitations, their resale value will be significantly impacted. For car owners, if they purchase a truck for freight transport via a loan, the depreciation of the vehicle after repaying the loan is equivalent to their net profit during that period. A higher residual value means more profit for the owner. Therefore, from this perspective, China 6 vehicles, which have a longer lifespan and greater road access rights, offer more advantages.

[NadiaLynn]

The main difference between China 5 and China 6 lies in the stringency of emission standards. The China 6 standard represents a significant upgrade, with nitrogen oxide (NOx) limits reduced from 180 mg/km under China 5 to below 60 mg/km under China 6, while carbon oxides are also halved. The testing methods differ—China 5 only used laboratory tests, whereas China 6 introduces Real Driving Emissions (RDE) testing to simulate real-world driving conditions more accurately. Technologically, automakers must install particulate filters or Selective Catalytic Reduction (SCR) systems to control pollution, increasing costs and making new cars several thousand yuan more expensive. However, the environmental benefits are substantial, as urban traffic restrictions are stricter for China 5 vehicles, while China 6 vehicles can pass smoothly. In terms of fuel, China 6 is more compatible with E10 ethanol gasoline. Long-term, China 6 vehicles have higher resale value, especially in license-plate-restricted areas where used car prices remain more stable. Overall, this represents technological progress contributing to reducing smog.

[MacJulianna]

Considering China 5 or China 6 standards when buying a car has significant economic implications. China 6-compliant new cars are typically at least 5,000 RMB more expensive due to manufacturers adding new technology costs. In the used car market, China 5 vehicles depreciate faster because of tightening emission policies, with many cities like Beijing and Shanghai imposing restrictions on China 5 models. Maintenance costs for China 6 vehicles are slightly higher, as the GPF system may require replacement, but the intervals are longer and fuel consumption is marginally better. Insurance and daily driving show no noticeable differences. If you're on a tight budget, China 5 vehicles are cheaper to purchase and suitable for short-term use; for long-term ownership, China 6 is more cost-effective, with better resale value and no urban driving restrictions. With policy support, China 6 vehicles will have better future support and higher trade-in value. Fuel costs remain the same, so don't worry too much about the details.

[OKhloe]

From an environmental perspective, the difference between China 5 and China 6 is significant. China 6 emission limits are much stricter, with nitrogen oxides reduced by half and fine particulate matter lower, significantly improving air pollution. In cities, China 6 vehicles are not subject to traffic restrictions, offering more freedom of movement. Nationally, policies promote China 6 to reduce carbon emissions, and as someone who cares about the environment, choosing a China 6 vehicle is a more responsible choice. Technologically, RDE testing ensures real-world emissions compliance, unlike China 5 which relied solely on laboratory tests. Simply put, China 6 represents green progress.